Upstream changes to the way PHB resources are registered
broke the resource fixup for FSL boards.

We can no longer rely on the resource pointer array for the PHB's
pci_bus structure, so let's leave it alone and go straight for
the PHB resources instead. This also makes the code generally
more readable.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>